However, these initial conclusions do not appear to have stood the test of time. Some early XMM-Newton data already provided results that conflicted with the initial paradigm of a relatively uniform \(\alpha \) -element and peaked Fe distribution in the IGrM: no gradient in Si/Fe was seen in NGC5044, comparing the regions within and beyond 48 kpc from the BGG [1]}; a constant and close to Solar \(\alpha \) /Fe out to at least 100 kpc was reported in NGC507 [2]}; and [3]} found that all measured abundances (O, Mg, Si, S, and Fe) in the group RGH80 showed a monotonic decrease with radius. In all these three cases, \(f_{\rm Fe,Ia}\)  was inferred to be in the range of 70–85%, assuming a model consisting of simple linear combinations of SNIa and SNcc. Therefore, although most Fe is being supplied indeed by SNIa, there did not appear to be a significant change in \(f_{\rm Fe,Ia}\)  with radius, or from system to system.
Similar conclusions were starting to be reached in galaxy clusters as well [4]}, [5]}, [6]}, [7]}.
